What is the difference between a painting and a picture? Two artists exhibiting this month demonstrate how artists can vacillate between both extremes to the benefit and satisfaction of the viewer. Both Michael Dailey at Francine Seders Gallery and Dion Zwirner at Davidson Galleries make abstract paintings with strong landscape references right down to their titles. However, the closer an abstract work comes to realistic imagery (sky, water, land, etc.), the more it is in danger of becoming a picture rather than a painting.

Of course, it is the prerogative of the artist to want to have it both ways. For both Dailey and Zwirner, such creative indecision or willful contradictions can lead to new territories of personal expression. It all depends on how the basic building blocks of abstract art are handled: color, form, composition, surface and touch.

Dailey, 66, seems at first more the modernist, that is, a painter who not only rejects blatant, identifiable imagery, but one who accepts the physical limitations of modernist painting. In this sense, a painting is no more and no less than a flat, two-dimensional surface with an arrangement of colors and forms, to paraphrase 19th-century French artist Maurice Denis.

Exhibit review Michael Dailey, 11 a.m.-5 p.m. Tuesdays-Saturdays, 1-5 p.m. Sundays, through Jan. 9, closed Dec. 25, 26 and Jan. 1, Francine Seders Gallery, 6701 Greenwood Ave. N., Seattle (206-782-0355 or www.sedersgallery.com). Dion Zwirner, 11 a.m.-5:30 p.m. Tuesdays-Saturdays, through Dec. 24, Davidson Galleries, 313 Occidental Ave. S., Seattle (206-624-7684 or www.davidsongalleries.com).

Dailey's 14th solo exhibition in Seattle since 1966 has all the hallmarks of what viewers have come to admire and expect from his art over the years. The large and small rectangular formats have broad, central expanses of one predominating color with multicolor accents on the edges and often near the bottom and top.

For this show, Dailey has concentrated on smaller acrylics on paper, with just a few 2-by-3-foot canvases and three larger works averaging 3 by 4 feet in size. While still uniformly frail and delicately nuanced, the sequence of 30 works points up the retired University of Washington professor's movement toward greater structure and stricter, marked-off sections of color.

Are the works of this artist really abstract paintings or might the future see them as conventional, late 20th-century landscapes? With titles like "Alaska Landscape," "Beach Landscape," "Northern Meadow" and "Dark Sea," Dailey's submerged realistic intentions are clear. Coupled with horizon lines and putative clouds, they undercut any flatness or sense of pure abstraction according to Denis' definition.

RICHARD NICHOL Dion Zwirner's "Rialto" (2004), oil on canvas, at Davidson Galleries.

Dion Zwirner, 57, trained with William Cumming at Cornish College before her graduate work at the San Francisco Art Institute. Once a figurative artist, Zwirner is trying hard to balance landscape references with abstraction. Like Dailey, she has her hits and misses, even within such a handsome and remarkably consistent body of work. Instead of Dailey's airy clouds, Zwirner uses water and earth as her signature allusions to the real world. The 16 oils on paper, canvas and wooden panel take on a Northwest look as a result, somewhat similar to veteran abstract painter Kathleen Gemberling Adkison of Spokane.

Unlike Dailey's built-up acrylic passages that can occasionally be clotted or globby, Zwirner's oils are at once sensuous and muscular. The telltale signs of a conventional picture are present in her work, too, though: horizon lines, upper-area skies and jagged, rocklike shapes. But, in works like "Rialto," "Apuntes #5," and "Red Tide" (all 2004), the gushes of a waterfall or dribbles of a stream dominate the surface.

Such liquid movement frees up the composition and, in an impressive material feat, draws more attention to painterly activity than to pictorial residue. In her own way, Zwirner has turned her pictures into painting.